Prognostic Implications of Fluid Balance in ST Elevation Myocardial Infarction Patients Complicated by Cardiogenic Shock

Introduction: A positive fluid balance has been associated with worse outcomes among patients admitted to general intensive care units, however no information is present to date on its possible prognostic implications in critically ill patients due to myocardial ischemia. We analyzed the relation of a positive fluid balance and its persistence over time to in-hospital outcomes among patients with cardiogenic shock (CS).

Methods: We retrospectively studied fluid intake and output for 96 hours following hospital admission in 48 consecutive adult patients with ST elevation myocardial infarction(STEMI) complicated by CS. Fluid overload was defined as more than a 5% increase in body weight relative to baseline. Patients records were assessed for in-hospital adverse outcomes as well as 30 day all-cause mortality.

Results: fluid overload was present in 15/48 patients ( 31%). Patients with fluid overload were less likely to undergo successful weaning from mechanichal ventilation, more likely to have acute kidney injury, need for new intubation,less likely to have renal recovery and had longer hospitalization (P< 0.05 for all). Patients with fluid overload had significantly higher 30 day mortality (73% vs. 15% ;P<0.001). In a multivariate logistic regression model for every 1 liter increase in fluid overload, the adjusted risk for 30 day mortality increased by 48% (OR=1.48, 95% CI 1.09-2.02; P=0.01).

Conclusions: A positive fluid balance was strongly associated with a higher 30-day mortality in STEMI patients complicated by CS.